In pictures: Routemaster retrospective

With the retirement of the Routemaster another London icon - the bus conductor - will also pass into history.

Although ticket machines like the one pictured have long been replaced by modern electronic versions, conductors like Kathy are regarded by many as a protective presence against crime and vandalism, as well as a source of information and help.

"I often built up a rapport with conductors while I was working," says Ralf. "Some would even introduce me to the passengers and explain what I was doing."